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arXiv · 1008.1106

Influence of superohmic dissipation on a disordered quantum critical point

Thomas Vojta·J. A. Hoyos·Priyanka Mohan·Rajesh Narayanan
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Abstract

We investigate the combined influence of quenched randomness and dissipation on a quantum critical point with O(N) order-parameter symmetry. Utilizing a strong-disorder renormalization group, we determine the critical behavior in one space dimension exactly. For superohmic dissipation, we find a Kosterlitz-Thouless type transition with conventional (power-law) dynamical scaling. The dynamical critical exponent depends on the spectral density of the dissipative baths. We also discuss the Griffiths singularities, and we determine observables.

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Thomas Vojta, J. A. Hoyos, Priyanka Mohan, Rajesh Narayanan. 2011-02-17. Influence of superohmic dissipation on a disordered quantum critical point. https://doi.org/10.1088/0953-8984%2F23%2F9%2F094206

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